JP2919866B2 - Fault location method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method and an apparatus (hereinafter referred to as a fault locating method for a transmission line).
More particularly, the present invention relates to a method and an apparatus for locating a fault that can improve the locating performance at the time of multiple accidents over two transmission lines.

[Prior art] Conventionally, as a measure to improve the accuracy of fault point location,
As disclosed in Japanese Patent No. 50262, a so-called impedance calculation type using the voltage and current of the
Many methods have been proposed, such as a method for locating a difference between lines in two parallel lines as disclosed in JP-A-61-189469. In recent years, many types of such fault locating devices have been put to practical use using microcomputers.

For practical use, a configuration is adopted in which a location method with the highest location accuracy is selected according to a failure mode (for example, a short-circuit failure, a ground fault, etc.), and a calculation result is output. This is due to the limitation of the calculation processing time.

Conventionally, this selection uses the local line voltage for a short-circuit fault and the local phase voltage for a ground fault, and detects the drop in the local voltage when a transmission line fails. Then, 1. Selection of the optimal orientation calculation method 2. Selection of the orientation calculation for the faulty phase was carried out to solve the problems due to improvement of the orientation accuracy and limitation of the operation processing time.

When selecting the orientation, select the short-circuit impedance using the line voltage and current for short-circuit faults, and select the ground-fault impedance using phase voltage and current during one-line operation for ground faults. When two circuits are operated, the calculation of the zero-phase difference current between the circuits is performed.

[Problems to be solved by the invention] However, in the case of a multiple accident case that spans two lines,
In particular, in the case of a fault with a different ground fault, a short-circuit fault is determined, and a short-circuit impedance location is selected and a fault point location calculation is performed. Point orientation was not possible.

For this reason, conventionally, multiple accidents have been treated as non-locating targets, and even if the calculation result was output, the search for a fault point had to rely on patrol by input.

However, this patrol work requires a great deal of labor. Therefore, there is a strong demand for the realization of an accurate failure point locating device for labor saving.

An object of the present invention is to determine the nature of an accident that has occurred in an area to be located in a transmission line system, and to efficiently determine a fault point according to the nature of the accident, even in an accident case involving two or more lines. It is an object of the present invention to provide a method and a device for a failure point of a transmission line system that can be well implemented.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for activating an accident point locating method, which firstly sets a current in each phase on a self-end side which is a terminal in a transmission system to be located. And input the current information of each phase on the other end side, which is a terminal for transmitting and receiving power to and from the own end side, for each of the current of each phase on the own end side and the current of each phase on the other end side. The difference is calculated, and when the calculated value exceeds a set value, an accident detection signal is output to detect that an accident has occurred in the phase of the line.

Next, for each phase of all lines in the transmission system to be located,
The number of lines in which an accident has occurred is determined based on the combination of the presence or absence of the detection of the accident phase. Then, based on this determination result,
Select a location calculation method to perform fault location.

Further, as an apparatus for achieving the above-mentioned object, the present invention provides a difference calculating means for calculating a difference between a current at its own end and a current at the other end connected by a transmission line to be located for each phase. And fault location determining means for determining a fault phase using the calculation result; and fault location starting means for determining a fault condition from the determination result and selecting a fault location mode and selecting a fault location phase. A point location device is provided.

Further, according to the present invention, a fault point locating device provided on one end side of the monitoring target area of the transmission line and performing a fault locating operation, and provided at both ends of the monitoring target area, Current detecting means for detecting the current and supplying current information to the failure point locating device, and the current information detected by the current detecting means at the end where the failure point locating device is not provided. Signal transmission means for transmitting, and the fault point locating device performs difference calculation means for calculating a difference between a current at its own end and a current at the other end connected by a transmission line to be monitored for each phase. An accident phase judging means for judging an accident phase by using the operation result; and an orientation operation starting means for judging a failure mode from the judgment result, selecting an orientation operation mode and selecting an orientation operation phase. Wire fault monitoring system Beam is provided.

Further, a difference calculating means for performing a calculation for each phase for calculating a difference between the current at the own end and the current at the other end connected by the transmission line to be monitored, and an accident determining the accident phase using the operation result. A transmission line fault comprising: a phase determination unit; and a mode determination unit configured to determine a failure mode based on a combination of presence / absence of the failure phase detection for each phase of all circuits in the monitored area based on the determination result. An aspect determination device is provided.

[Operation] The present invention determines the difference between the current at the own end and the current at the other end for each phase when an accident occurs in the protection target area of the transmission line system, and when the difference exceeds a set value, It is determined that an accident has occurred in the relevant phase. Further, it is determined from the combination of the determination results for each phase whether the accident is for one line or for two or more lines. At the same time, it is determined whether a ground fault or a short circuit has occurred. Then, based on the determination, an optimum location calculation method is selected in accordance with the type of the accident in the accident phase, and the fault point location calculation for the accident line is performed.

As a result, not only a single fault of the transmission line but also a multiple fault is performed without performing an improper localization calculation based on an erroneous determination, and performing a fault point localization calculation in a manner optimal for the aspect of the fault. It becomes possible.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows the overall configuration of the power transmission system in which three-phase AC transmission is displayed as a single line.

In FIG. 1, a terminal A on the self-end side is provided with an in-house bus 1, current transformers 2, 3, an analog processing device 9a, and the like. On the side of the terminal B on the other end side for transmitting and receiving power to and from the terminal A, an in-house bus 6, current transformers 7, 8 and an analog processing device 9b are provided. Terminal A and terminal B are connected via transmission lines 11 and 12. Further, a failure point locating device (hereinafter abbreviated as FL device) 4 is provided on the terminal A side.

The current transformers 2, 3 are connected to an analog processing device 9a, and the current transformers 7, 8 are connected to an analog processing device 9b.

Each of the analog processing devices 9a and 9b includes a sampling and holding circuit that samples the current sent from the current transformer at a constant cycle, a filter that removes noise, an A / D conversion circuit that converts an analog signal into a digital signal, and the like. You. In addition, a level conversion circuit for converting the current information into a signal of a level that can be easily handled by the FL device 4 may be provided. However, on the A terminal side of the installation end of the FL device 4, the analog processing device 9a can be incorporated in the FL device 4.

The FL device 4 is connected to the signal transmission device 5, and the analog processing device 9b is connected to the signal transmission device 10. Each of the signal transmission devices 5 and 10 has a signal transmission path 13
FL device 4 connected to the A terminal
Is configured to receive the current information of the other end through this.

With such a configuration, a transmission line monitoring system is configured. As described later, it is preferable that the transmission line monitoring system be configured by using a computer system for the FL device 4 as a component thereof.

The FL device 4 includes, as shown in FIG.
It is composed of an accident phase detection circuit 14, an orientation calculation start circuit 15, an orientation calculation circuit 16, an orientation value output circuit 17 and the like for detecting an accident of the transmission line 11, 12 when an accident occurs in the transmission lines 11, 12.
It is configured to locate the distance from the A terminal to the accident point and output the result.

In addition, the FL device 4 has the phase current information 18 of the transmission line 11 at its own end from the current transformer 2, the phase current information 19 of the transmission line 12 from the current transformer 3, and the signal transmission device 5. Is input with each other's respective phase current information 20.

As shown in FIG. 3, the fault phase detection circuit 14 compares a difference circuit 141 for calculating the difference between the same-phase currents of the self-end and the other end with the same-end current and determines whether the difference value exceeds a set value. And a comparator 142 for determining the accident phase
1 to 14c2.

Among these determination circuits 14a1 to 14c2, the determination circuit for the transmission line 12 has 14a1 for the a phase, 14b1 for the b phase, and 14c1 for the c phase. In the determination circuit for the transmission line 11, the phase a is 14a2, the phase b is 14b2, and the phase c is 14c2. The current input of the transmission line 11 to each of the difference circuits 141 is 18a for the a phase, 18b for the b phase, and 18c for the c phase. The current input of the transmission line 12 at its own end is
The phases 9a and b are 19b, and the phase c is 19c.

The comparator 142 compares the difference value output from the difference circuit 141 with a set value, and outputs a logic signal according to whether the difference value exceeds the set value. That is, for example, “1” is output when the difference value exceeds the set value, and “0” is output when the difference value does not exceed the set value.

Here, 20a1, 20b1, 20c1, 20a2, 20b2, and 20c2 are current information transmitted from the other ends, respectively, and are, in order, the a-phase a, b-phase, and c-phase of the transmission line 12 and the counterpart a of the transmission line 11. Phase, b phase, c
This is phase current information.

14a1o to 14c2o are signal lines for outputting the determination result of the fault phase determination circuit 14, and "1" is output for the determined fault phase. For example, when an accident occurs in the phase a of the transmission line 11, "1" is output to the signal line 14a2o. Similarly, when an accident occurs in the phase b of the transmission line 12, "1" is output to the signal line 14b1o, and the information is used in the orientation calculation activation circuit 15.

The accident phase determination circuit 14 can be configured by a computer system such as a microcomputer. For example, a processor that executes calculations, determinations, and the like, a program memory that stores programs to be executed by the processors, a data memory that stores input data, calculation results, and the like, and an I / O interface that connects to the outside. It can be provided and configured.

The orientation calculation activation circuit 15 uses the output signal from the accident phase determination circuit 14 to determine the aspect of the accident. FIG. 4 shows the determination function of the orientation calculation starting circuit 15 together with the processing flow.

In the figure, a multiple fault judging unit 21 for judging whether there is one line fault or two or more faults, a ground fault short judging unit 22 for judging one line fault or two or more faults, The same-phase and different-phase accident determination unit 23 that determines whether the fault is a different phase fault, the ground fault location starting units 24 and 26 that execute the ground fault location start for performing the location calculation suitable for the ground fault accident, and the short-circuit fault It is configured to include short-circuit orientation starting units 25 and 27 that execute short-circuit orientation activation for performing suitable orientation operation.

The orientation calculation activation circuit 15 determines each of the determination units 21 based on a logical combination of the determination results output from the accident phase determination circuit 14.
Since the determinations in steps (1) to (23) are performed, the computer system can be configured. For example, in the same manner as described above, regarding the above-described accident phase determination circuit 14, a processor that performs determination, control, and the like,
27, a program memory for storing a program for executing the functions of .about.27 and preset judgment reference data, a data memory for holding the judgment result, and the like.

This computer system does not need to be provided exclusively for the orientation calculation activation circuit 15. For example, a configuration may be used in common with the computer system forming the accident phase determination circuit 14, or a configuration may be used in common with the computer system forming the orientation calculation circuit 16.

Note that the orientation calculation starting circuit 15 may be configured by a combination of logic circuits.

The orientation calculation circuit 16 includes a ground fault orientation calculation means and a short-circuit orientation calculation means. These means can be configured by a computer system as described above.

Further, the output circuit 17 has a function of outputting a calculation result or the like of the orientation calculation circuit 16 as a control signal for a circuit breaker or the like. Further, it may be configured to include a display, a printer, and the like for displaying the calculation result.

 Next, the operation of this embodiment will be described.

The analog processing circuits 9a and 9b periodically sample current information from the current transformers 2, 3, and 7, 8, respectively.
Output as digital value. Thus, the presence or absence of an accident is monitored.

The output from the analog processing circuit 9a is input to the FL device 4, and the output from the analog processing device 9b is transmitted from the signal transmission device 10 to the transmission line 13, received by the signal transmission device 5, and
Input to the device 4.

In the accident phase detection circuit 14, an accident phase is detected by the difference circuit 141 and the determination circuit 142 described above. Then, the detection result is output from the signal lines 14a1o to 14c2o.

In the orientation calculation activation circuit 15, the multiple accident determination unit 21
The judgment outputs of the fault phase judging circuit 14 are fetched from the signal lines 14a1o to 14c2o at a fixed period, and it is judged whether a single line failure or a multiple failure of two or more lines based on a combination of the outputs.
For example, if an accident occurs in the phase a of the transmission line 11, the signal line
Since “1” is output to 14a1o, all signal lines 14a1o to 14c2o
If there is only one signal of "1", it is determined that one line has failed. Here, at the same time, for example, if an accident also occurs in the phase b of the transmission line 12, "1" is also output to the signal line 14b1o, so that it is determined that two lines have failed.

In the case of a one-line failure, the ground fault short-circuit determination unit 22 determines whether the failure is a one-line failure or a failure of two or more lines. Further, in the case of multiple accidents, the same-phase / unknown phase accident determination unit 23 determines whether the fault is the same-phase fault or a different-phase fault. For example, in the above-described example, since “1” is output to the signal line 14a2o and the signal line 14b1o, it is determined that a different phase fault has occurred.

Then, in the case of a one-line fault, the ground fault locating start unit 24 executes the ground fault locating start, and in the case of a fault of two or more wires, the short-circuit locating starting unit 25 executes the short-circuit locating start. Further, in the case of the same-phase fault, the ground fault locating start unit 26 executes the ground fault locating drive, and in the case of the strange phase fault, the short-circuit locating starting unit 27 executes the short-circuit location activating. In these cases, signal line 14
Since a1o to 14c2o correspond to the phases of the transmission lines 11 and 12, the accident phase to be subjected to the orientation calculation can be specified by the signal line name that outputs the judgment result indicating the accident.

On the basis of this start-up result, in the orientation calculation circuit 16,
The respective orientation calculations that are started are executed. Then, a control signal or the like is output from the output circuit 17 as the orientation result.

As described above, according to the present embodiment, it is possible to distinguish between a ground fault and a short-circuit accident in the case of one-line failure as well as in the case of two-line failure, and select an appropriate failure point location calculation method. be able to.

Note that, in the above-described embodiment, a case where two transmission lines to be monitored are provided has been described, but the present invention is also applicable to a multi-line having three or more lines.

Further, in the above-described embodiment, an example has been described in which each component of the FL device 4 is configured by a computer system, but the entire configuration may be configured by a single computer system.

[Effects of the Invention] As described above, according to the present invention, the fault phase is determined by the differential determination from the currents on the self-end side and the partner end side, and an appropriate orientation calculation is executed according to the determination result. Because
In addition to being able to accurately determine and locate the location phase, it is also possible to locate multiple faults that have conventionally been excluded from location.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of an embodiment of a FL device, and FIG. 3 is an embodiment of the configuration of an accident phase detection circuit. FIG. 4 is a block diagram showing a configuration of an embodiment of the orientation calculation starting circuit. 1,6… In-house bus, 2,3,7,8… Current transformer, 11,12… Transmission line, 4
… FL device, 5,10… Signal transmission device, 9a, 9b… Analog processing device, 13… Transmission line, 14… Fault phase detection circuit, 15… Location operation start circuit, 16… Location operation circuit, 17… Output circuit.

Claims (4)

(57) [Claims] 1. The current of each phase on the self-end side and the current information of each phase on the self-end side in the transmission system to be located and the current information on each phase on the other end side. The difference is calculated for each of the currents of each phase on the side, and when the calculated value exceeds the set value, it is detected that an accident has occurred in the phase of the line concerned, and all A fault point locating method characterized by determining the number of lines in which an accident has occurred based on a combination of the presence or absence of the fault phase detection for each phase of a line, selecting a location calculation method, and performing a fault point location. 2. A difference calculation means for calculating a difference between a current at a self-end and a current at a counterpart end connected by a transmission line to be located, for each phase, and determining an accident phase by using the calculation result. A fault point locating device comprising: an accident phase judging means for judging; and a locating operation activating means for judging a failure mode from the result of the judgment and selecting a locating operation method and selecting an locating operation phase. 3. A fault point locating device provided at one end of a monitoring target area of a transmission line and performing a fault locating operation, and provided at both ends of the monitoring target area to detect a current for each phase. Current detection means for supplying current information to the failure point locating device, and a signal for transmitting the current information detected by the current detection means at the end where the failure point locating device is not provided to the failure point locating device. Transmission means, the failure point locating device, the difference calculation means for calculating the difference between the current of the self-end and the current of the other end connected by the transmission line to be monitored for each phase, this difference calculation means, An accident phase judging means for judging an accident phase by using the operation result, and an orientation operation starting means for judging a failure mode from the judgment result, selecting an orientation operation method and selecting an orientation operation phase. Transmission line fault monitoring system Stem. 4. A difference calculating means for calculating a difference between a current at its own end and a current at a counterpart end connected by a transmission line to be monitored for each phase, and determining an accident phase by using the calculation result. It is provided with: an accident phase judging means for judging; and a mode judging means for judging a mode of failure based on a combination of presence / absence of the detection of the accident phase for each phase of all lines in the monitoring target area from the judgment result. A device for determining the appearance of a power line accident.